XU 
PREFACE. 
f. 423. The division and divarication of the pinnae of 
Polypodium vulgare, especially at the lower end of the 
frond, are familiar to observers: see N.F. f. 14, 19, 29, 
and especially plate viii. In Osmunda regalis this divarica- 
tion of the branching costa constitutes a distinct variety. 
4. We come next in order to the leafy expansion or 
Lamina of the frond ; and in this part, the varieties of form 
and development may be truly called endless, arising some- 
times from excess, at others from defect of the part. If, 
for instance, the lamina is much enlarged in breadth, while 
the rachis and costa remain unchanged, the effect of undula- 
tion or frilling takes place, as frequently in the Hartstongue ; 
and, when this enlargement occurs in the forked divisions of 
the rachis and costae, some of the most elegant forms result, 
familiar to the cultivators of Ferns. Poly podium vulgare, 
var. Cambricum, for example, Scolopendrium vulgare, 
Standsfieldii, N.F., plate 54, cristatum, plate 50, and ramo- 
marginatum, f. 778. 
Under this head we place the tufted forkings of the Lamina, 
f 4a, so much admired in the crested male fern ; a rosette- 
like termination of every pinna, as well as of the apex of the 
frond, giving this fern, as well as Polystichum angulare, 
Athyrium filix-foemina, Lastrea dilatata, and other species, 
a conspicuously elegant character. 
Do these clustering rosettes ever appear upon the fronds ? 
In crested varieties of the Male Fern, the extremity of 
the frond and pinnules is often branched, and spreads 
like the feathered foot of the Ptarmigan, forming, with the 
crested termination, a corymb. 
The expansion and lengthening of the Lamina, without an 
equal enlargement of the costa, sometimes gives rise to a 
curving upwards and inwards of the margin of the pin- 
nules, as in Lastrea Fsenisecii ; which character, accom- 
panied by a tufted state of the usually short and decum- 
bent fronds, and the rough rigid narrow scales of the 
stem, has given this Fern so marked an ensemble as, if no 
